1. Field of the Invention
This invention relates to opto-acoustic transducers and in particular to an arrangement for converting speech signals into amplitude modulated optical signals.
2. Description of the Prior Art
One of the problems encountered with optical, i.e. optical fiber, telephone transmission systems, is the provision of an interfacing device between a conventional electric or electronic telephone subset. In present systems this interfacing device comprises a light source the output of which is modulated by an electrical signal derived from the information to be transmitted. A fiber optic switch is described by N. H. Leighton, Fiber Optic Shutter, IBM Technical Disclosure Bulletin, Vol. II, No. 18, January 1969, pp. 912-913. U.S. Pat. No. 2,835,744 describes the modulation of a light beam in response to sound signals in a microphone.